Fuel tank assembly for skid steer loaders

ABSTRACT

Rotationally molded component parts for a skid steer loader are disclosed wherein the parts provide specialized operative functions heretofore unrealized. A fuel tank structure includes both a tank body and a separate filler tube formed from a rotational molding process. The filler tube is connected to the fuel tank body by a fastening mechanism and an O-ring to provide a liquid-tight connection. The coolant recovery bottle formed with the rotational molding process incorporates an inwardly directed vent tube formed as an integral part of the recovery bottle. The container for the operator&#39;s manual is formed with the rotational molding process to incorporate a live hinge connecting a lid closable against the body of the container to provide a substantially dirt-free environment. Double walled light housings mounting front and rear lights serve as bumpers protecting the frame of the skid steer loader from damage from impact. The hydraulic reservoir tank is formed with a kiss-off structure interconnecting the opposing lateral sides of the reservoir tank to add strength and maintain integrity.

This is application is a continuation of application Ser. No.08/339,054, filed Nov. 14, 1994, now abandoned.

BACKGROUND OF THE INVENTION

This invention relates generally to the creation of non-metallic partsfor use on off-road vehicles, and, more particularly, to componentsformed by a rotational molding process to form component parts suitablefor use on skid steer loaders.

Rotational molding is a known process used for manufacturing plasticcomponents by first creating a mold formed in the shape of the componentto be formed, and then pouring a suitable quantity of powderedpolyethylene resin into the mold, after which the mold is closed, heatedto about 600° F. and slowly rotated for approximately 10 minutes toevenly distribute the resin to the periphery of the mold. The heatingprocess converts the powdered resin into an integral plastic sheeting,having a generally uniform thickness conforming to the shape of themold. The material thickness of the component part being formed isdependent on the amount of resin material first poured into the mold. Byprecise formation of the mold and careful calculation of the amount ofresin to be applied, a generally hollow polymer component can be formedfrom this process.

The rotational molding process has not been traditionally used inconstructing parts for off-road vehicles. Such component parts havetypically been cast of metal or formed from sheet metal to provide thedesired durability and function. Nevertheless, rotationally moldedcomponents are manufactured with significantly less cost thatcorresponding metallic parts and contain significantly less weight.Furthermore, the function of metallic components have heretofore notbeen capable of being duplicated, such as providing hinged closures,liquid-tight connections, vent tubes and high strength, large volumeliquid-tight vessels.

Accordingly, it would be highly desirable to provide a means forconstructing rotationally molded components to provide live hinges,liquid tight connections, vessels with splash-proof vent tubes andkiss-offs in large volume liquid-tight vessels to improve the lateralstrength thereof to permit the use of such components in specialty areason skid steer loaders.

SUMMARY OF THE INVENTION

It is an object of this invention to overcome the aforementioneddisadvantages of the prior art by providing rotationally moldedcomponents for skid steer loader construction.

It is another object of this invention to provide a rotationally moldedfuel tank for a skid steer loader.

It is a feature of this invention that the filler tube and the fuel tankbody can be rotationally molded as separate components and assembled ina liquid-tight manner.

It is an advantage of this invention that the connection between thefiller tube and the rotationally molded fuel tank will not leak fuelexternally of the fuel tank.

It is another object of this invention to provide a rotationally moldedcoolant recovery bottle for use on a skid steer loader.

It is another feature of this invention that the coolant recovery bottleis provided with a vent tube integrally formed into the body of thevessel.

It is another advantage of this invention that the vent tube for therotationally molded coolant recovery bottle is substantiallysplash-proof.

It is still another object of this invention that the operator's manualstorage container for a skid steer loader can be rotationally molded.

It is still another feature of this invention that the operator's manualstorage container includes a lid connected to the body of the containerby a live hinge formed during the rotational molding process.

It is still another advantage of this invention that the lid of therotationally molded operator's manual storage container closes againstthe body of the container to provide a substantially clean environmentfor the storage of the operator's manual.

It is yet another object of this invention to provide a double walledlight housing for both the front and rear lights of a skid steer loader.

It is yet another feature of this invention that the double walled lighthousings serve as a bumper to absorb damage to protect the metallicframe of the skid steer loader during appropriate impacts.

It is yet another advantage of this invention that the front and rearlights can be mounted in the light housings and retained by a standardbezel.

It is a further object of this invention to provide a large volumehydraulic reservoir tank for a skid steer loader that is formed from arotational molding process.

It is a further feature of this invention that the hydraulic reservoirtank is formed with a kiss-off interconnecting the two opposing lateralsides of the tank to increase the strength of the tank body and preventbulging of the sides of the tank due to the volume of hydraulic fluidcontained therein.

It is a further advantage of this invention that the hydraulic reservoirtank can be formed with substantially large lateral sides co-joined byan internal kiss-off structure to maintain the integrity of the tankwhen utilized in a relatively confined space on a skid steer loader.

It is yet a further object of this invention to provide rotationallymolded component parts for a skid steer loader which is durable inconstruction, inexpensive of manufacture, carefree of maintenance,facile in assemblage, and simple and effective in use.

These and other objects, features and advantages are accomplishedaccording to the instant invention by providing rotationally moldedcomponent parts for a skid steer loader wherein the parts providespecialized operative functions heretofore unrealized. A fuel tankstructure includes both a tank body and a separate filler tube formedfrom a rotational molding process. The filler tube is connected to thefuel tank body by a fastening mechanism and an O-ring to provide aliquid-tight connection. The coolant recovery bottle formed with therotational molding process incorporates an inwardly directed vent tubeformed as an integral part of the recovery bottle. The container for theoperator's manual is formed with the rotational molding process toincorporate a live hinge connecting a lid closable against the body ofthe container to provide a substantially dirt-free environment. Doublewalled light housings mounting front and rear lights serve as bumpersprotecting the frame of the skid steer loader from damage from impact.The hydraulic reservoir tank is formed with a kiss-off structureinterconnecting the opposing lateral sides of the reservoir tank to addstrength and maintain integrity.

BRIEF DESCRIPTION OF THE DRAWINGS

The advantages of this invention will be apparent upon consideration ofthe following detailed disclosure of the invention, especially whentaken in conjunction with the accompanying drawings wherein:

FIG. 1 is a left, front perspective view of a skid steer loaderincorporating the principles of the instant invention, a portion of theexternal structure of the skid steer loader being broken away to revealthe location of the fuel tank and filler tube formed from the rotationalmolding process;

FIG. 1A is a partial cross-sectional view of the fuel tank assemblydepicting the connection of the filler tube to the fuel tank body toprovide a liquid-tight connection therebetween;

FIG. 1B is a partial exploded view of the fuel tank assembly depictingthe connection of the filler tube to the tank body corresponding to theembodiment of FIG. 1A;

FIG. 1C is a partial cross-sectional view of the fuel tank assemblydepicting an alternative embodiment of the connection of the filler tubeto the fuel tank body to provide a liquid-tight connection therebetween;

FIG. 1D is a partial exploded view of the fuel tank assembly depictingthe alternative connection of the filler tube to the tank bodycorresponding to the embodiment of FIG. 1C;

FIG. 2 is a left, front perspective view of a skid steer loaderincorporating the principles of the instant invention, a portion of theexternal structure of the skid steer loader being broken away to revealthe location of the coolant recovery bottle formed from the rotationalmolding process;

FIG. 2A is a perspective view of the coolant recovery bottle shown inFIG. 2;

FIG. 2B is a side elevational view of the coolant recovery bottle shownin FIG. 2A;

FIG. 2C is an enlarged partial cross-sectional view of the vent tubecorresponding to circle C of FIG. 2B;

FIG. 3 is a left, front perspective view of a skid steer loaderincorporating the principles of the instant invention, a portion of theexternal structure of the skid steer loader being broken away to revealthe location of the seat pan and the attached operator's manualcontainer formed from the rotational molding process;

FIG. 3A is an enlarged left front perspective view of the skid steerloader seat pan and operator's manual container affixed thereto asdepicted in FIG. 3;

FIG. 3B is an enlarged side elevational view of the operator's manualcontainer with the movement of the lid being shown in phantom, portionsof the seat pan being broken away for purposes of clarity;

FIG. 3C is an enlarged side elevational view of the top portion of theoperator's manual container as ejected from the mold, the cut lines forforming the lid portion being shown in dotted lines;

FIG. 4 is a left, front perspective view of a skid steer loaderincorporating the principles of the instant invention, the location ofthe front and rear light housings formed from the rotational moldingprocess being encircled for purposes of clarity;

FIG. 4A is an enlarged perspective view of the front light housingcorresponding to circle A in FIG. 4;

FIG. 4B is an exploded view of the front light housing;

FIG. 4C is an enlarged cross-sectional view of the front light housingshown in FIG. 4A;

FIG. 4D is an enlarged exploded view of the rear light housingcorresponding to circle D in FIG. 4;

FIG. 4E is an enlarged cross-sectional view of the rear light housingshown in FIG. 4;

FIG. 5 is a left, front perspective view of a skid steer loaderincorporating the principles of the instant invention, a portion of theexternal structure of the skid steer loader being broken away to revealthe location of the hydraulic reservoir tank formed from the rotationalmolding process;

FIG. 5A is an enlarged perspective view of the hydraulic reservoir tankshown in FIG. 5;

FIG. 5B is a side elevational view of the hydraulic reservoir tank shownin FIG. 5A; and

FIG. 5C is an enlarged partial cross-sectional view of the kiss-offportion of the hydraulic reservoir tank corresponding to lines C--C ofFIG. 5B.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings and, particularly, to FIGS. 1-5, arepresentative view of a skid steer loader incorporating the principlesof the instant invention can best be seen. Any left and right referencesare used as a matter of convenience and are determined by standing atthe rear of the skid steer loader and facing the forward end in thenormal direction of travel. The skid steer loader 10 comprises a fixedwheeled vehicle having a frame 11, opposing pairs of front and rearwheels 13, 14 rotatably supported by the frame for movement over theground.

As is conventional in such machines, the wheels 13, 14 of the skid steerloader 10 are rotatably driven by hydraulic motors (not shown)operatively powered from an engine 12 supported from the frame 11.Steering of the skid steer loader 10 is accomplished by differentialdriving of opposing left and right side wheels 13, 14 in a conventionalmanner through the use of a pair of control sticks 15. The frame 11defines an operator's cab 17 in which the operator sits to maneuver theloader 10. A work implement, shown in FIGS. 1-5 as a bucket 18, ispowered in a conventional manner by hydraulic cylinders 19 to locate thework function immediately forwardly of the operator's cab 17.

Referring now to FIGS. 1 through 1D, the fuel tank assembly 20constructed according to the principles of the instant invention canbest be seen. The fuel tank assembly 20 consists primarily of the fueltank body 22 and the attached filler tube 25, both of which have beenmanufactured from the rotational molding process to define hollow bodieshaving a predetermined wall thickness. The tank body 22 is of a suitableshape to fit within the narrow confines between the frame 11 and theengine 12 and is rotationally molded to define an inlet opening 23 and afuel line opening (not shown) near the bottom of the tank to withdrawfuel therefrom in a conventional manner for use by the engine 12.

The inlet opening 23 is located near the top of the tank body 22 forobvious reasons and is defined by a flange 24 projecting outwardly fromthe tank body 22. As with all other portions of the tank body, and allother rotationally molded parts, the flange 24 is formed during themanufacturing process and is an integral part of the tank body 22. Thefiller tube 25 is a hollow cylindrical member having an opening anopposing ends to form a conduit for the introduction of fuel into thetank body 22. The filler tube 25 includes a neck 26 having an outsidediameter substantially equal to the inside diameter of the flange 24defining the inlet opening 23 so that the filler tube 25 can fit snuglyinto the flange 24. The outside diameter of the filler tube 25 ispreferably of the same outside diameter and shape of the flange 24 so asto give the appearance of a continuous extension of the flange 24.

As depicted in the preferred embodiment of FIGS. 1A and 1B, the neck 26of the filler tube 25 and the flange 24 is formed with a groove 27 tofit an O-ring 29 positioned within the groove 27 and compressed betweenthe flange 24 and the neck 26 to prevent leakage of fuel therebetween. Aself-tapping screw 28 extends through a suitable hole formed in theflange 24 and neck 26 to prevent the filler tube 25 from separating fromthe tank body 22. Preferably, the filler tube 25 adjacent the inletopening 25a is provided with threads 25b to permit engagement of a fuelcap (not shown) for sealing off the fuel tank assembly 20 when fuel isnot being introduced into the fuel tank body 22.

An alternative embodiment of the connection between the filler tube 25and the tank body 22 is depicted in FIGS. 1C and 1D. As previouslydescribed, the filler tube 25 includes a neck 26 that snugly fits withinthe flange 24 to mate thereagainst. Instead of using the screw 28 andO-ring 29, the filler tube 25 is fixed to the flange 24 by a clampingapparatus 30 consisting of a rubber sleeve 32 and a pair of hose clamps33, 34. The first hose clamp 33 compresses the rubber sleeve 32 againstthe outside diameter of the flange 24, while the second hose clamp 34compresses the rubber sleeve 32 against the filler tube 25. As a result,the joint between the filler tube 25 and the flange 24 is sealedexternally, rather than internally by the O-ring 29, although the O-ring29 could still be utilized, and the clamping apparatus 30 provides apositive clamping force to affix the filler tube 25 to the tank body 22.

Referring now to FIGS. 2 through 2C, the coolant recovery bottle 35constructed according to the principles of the instant invention canbest be seen. As with the fuel tank assembly 20, the coolant recoverybottle 35 is manufactured with a rotational molding process in which amold (not shown) is constructed to conform to the desired shape of thebottle 35. A predetermined amount of powdered resin in poured into themold and rotated and heated to form the hollow bottle 35 having amounting flange 36 with holes 36a therethrough for the passage offasteners (not shown) to mount the bottle 35 to the frame 11 of theloader 10, a threaded inlet opening 37 for the introduction of coolantinto the bottle 35, an connecting line opening 38 for the connection ofa line (not shown) from the engine radiator (not shown).

To vent the bottle 35 to the atmosphere, as is necessary for coolantrecovery bottles 35, the recovery bottle 35 is also formed with aninternal vent 39 projecting inwardly into the interior of the bottle 35.Since formed as part of the rotational molding process, the interiorvent 39 is an integral part of the bottle 35 structure. By reason of thevent 39 extending substantially perpendicular to the major axis of thebottle 35 and projecting a substantial distance into the interior of thebottle 35, the vent 39 is substantially spill-proof. Coolant splashingaround within the interior of the bottle will generally be at a levelsubstantially lower than the vent 39 and, as a result, will usually bedirected away from the perpendicular axis of the vent 39 to prevent theexternal spillage of the coolant through the vent 39.

Referring now to FIGS. 3 through 3C, the operator's manual container 40constructed according to the principles of the instant invention canbest be seen. The operator's manual is occasionally needed by theoperator of the skid steer loader 10 while at a remote location. To keepthe operator's manual clean and dry, the skid steer loader 10 isequipped with a operator's manual container 40 positioned behind theseat (not shown) which is mounted on a seat pan 41 to permit positionaladjustment of the seat (not shown) relative to the frame 11. Theoperator's manual container 40 is affixed to the seat pan 41 immediatelybehind the seat (not shown) for convenient access by the operator.

Referring specifically to FIGS. 3B and 3C, the operator's manualcontainer 40 is constructed with the rotational molding process as ahollow body. The top portion 43 of the container 40 is formed with aspecific shape, as best seen in FIG. 3C, with cut lines 44 to define thediscard portion 49 of the container 40. After the discard portion 49 iscut away from the molded container 40, a lid member 45 is defined withan upturned lip 46 that is depressible beneath the latch surface 47 torestrain the movement of the lid member 45. During the creation of themold, an indent edge was inserted at a location corresponding to thelower edge of the lid member 45. As a result, the container 40 is formedwith a linear portion 48 along the lower edge of the lid portion with amaterial thickness that is slightly less than the rather uniformthickness of the rest of the container 40. This linear portion 48 formsa live hinge that enables the lid member 45 to be rotated away from thecontainer 40, as depicted in phantom in FIG. 3B.

Referring now to FIGS. 4 through 4E, the front and rear light housingsconstructed according to the principles of the instant invention canbest be seen. The front light housing 50, depicted in FIGS. 4A through4C, is formed with a double wall construction at the top 51 and bottom52 to provide additional strength and resistance to damage from impact.A central member 53 divides the housing into a lower light chamber 54and an upper light chamber 55, both of which are open to the front ofthe housing 50. A light 56 can be mounted in either light chamber 54, 55and restrained in place by a bezel 59 detachably affixed by fasteners,representatively shown at 57, to the housing 50. Electrical wires 58 canpass through a suitable opening formed within the housing 50 to passthrough the frame 11 of the loader 10.

Referring specifically to FIGS. 4D and 4E, the rear light housing 60 canbe formed as an elongated member extending substantially the entirewidth of the loader along the rear of the frame 11. The rear lighthousing 60, like the front light housing 50, includes a double wallconstruction and defines a plurality of horizontally disposed lightchambers 65 open to the rear of the housing 60 away from the frame 11.Lights 66 can be selectively mounted in appropriate light chambers 65 toprovide the desired rear lighting effects. A rear bezel 69 is detachablyaffixed to the rear light housing 60 by fasteners, representativelyshown at 67, to retain the lights 66 in the corresponding light chamber65.

Because of their double wall construction, the front and rear lighthousings 50, 60 provide bumpers or corner protectors to protect theframe 11 of the skid steer loader 10 from damage from impact. Thelocation of the front light housings 50 at the respective upper frontcorners of the operator's cab 17 and of the rear light housing along therear of the operator's cab 17 protects the cab 17 and the frame 11 fromdamage from impact. The double walled housings 50, 60 absorb impact anddamage resulting therefrom to prevent the impact from reaching anddamaging the cab 17 or frame 11.

Referring now to FIGS. 5 through 5C, the details of the hydraulicreservoir tank 70 constructed according to the principles of the instantinvention can best be seen. The hydraulic reservoir tank 70 storeshydraulic fluid for the entire hydraulic system of the skid steer loader10. Since the loader 10 is driven through hydraulic motors (not shown)and is operatively powered through hydraulic cylinders 19, the hydraulicreservoir comprises a substantial volume of hydraulic fluid. Thisreservoir of hydraulic fluid is stored in the reservoir tank 70, whichis confined within the frame 11 of the loader 10.

Due to the unique shape of the hydraulic reservoir tank 70, as best seenin FIG. 5A and the substantial volume that must be contained within thetank 70, the opposing lateral sides 71, 73 off the tank are quiteexpansive in size. To prevent the lateral sides 71, 73 of the tank 70from bulging with the weight of the hydraulic fluid stored within thetank 70, the tank 70 is formed with an integral kiss-off member 75interconnecting the opposing sides 71, 73 and adding rigidity to thetank structure 70. Since the kiss-off member 75 is formed as part of therotational molding process, as best seen in FIG. 5C, the kiss-off member75 is an integral part of the tank and will not separate from theopposing lateral walls 71, 73.

It will be understood that changes in the details, materials, steps andarrangements of parts which have been described and illustrated toexplain the nature of the invention will occur to and may be made bythose skilled in the art upon a reading of this disclosure within theprinciples and scope of the invention. The foregoing descriptionillustrates the preferred embodiment of the invention; however,concepts, as based upon the description, may be employed in otherembodiments without departing from the scope of the invention.Accordingly, the following claims are intended to protect the inventionbroadly as well as in the specific form shown.

Having thus described the invention, what is claimed is:
 1. In an off-road vehicle having a wheeled frame adapted for movement over the ground; an engine supported by said frame to provide operative power for said vehicle; and a fuel tank assembly for storing a supply of fuel for use by said engine, an improved fuel tank assembly comprising:a molded polymer, hollow tank body having a inlet opening for the introduction of fuel into said tank body, said tank body including a flange extending outwardly from said tank body and defining said inlet opening; a molded polymer filler tube detachably fastened to said tank body at said inlet opening to form a joint therebetween, said filler tube extending outwardly from said tank body to direct fuel from a remote location into said inlet opening, said filler tube being formed with a neck having a shape corresponding to the shape of said flange and being sized to fit inside said flange to extend into said inlet opening, said filler tube being self supporting; means for sealing said joint between said filler tube and said tank body to prevent the passage of fuel therebetween; and a self-tapping screw interengaged between said flange and said neck of said filler tube for detachably connecting said filler tube to said tank body.
 2. The vehicle of claim 1 wherein said neck includes an annular groove formed therein, said sealing means further including an O-ring located within said groove to be compressed between said neck and said flange to seal said joint therebetween.
 3. A fuel tank assembly for use on a skid steer loader having a wheeled frame adapted for movement over the ground and an engine supported by said frame to provide operative power for said vehicle, comprising:a molded polymer, hollow tank body, said tank body including a flange projecting outwardly therefrom and defining an inlet opening for the introduction of fuel into said tank body; a molded polymer filler tube being engageable with said flange to form a joint therebetween, said filler tube including a neck having a shape and size to fit snugly within the inner circumference of said flange, said filler tube having an outside diameter adjacent to said flange, said filler tube outside diameter being substantially identical to the outside diameter of said flange to provide the appearance of said filler neck tube providing a smooth extension from said flange, said filler tube being self supporting; a self-tapping screw interconnecting said neck of said filler tube and said flange to detachably connect said filler tube to said flange and to seal said joint therebetween; and an O-ring positioned within a groove formed in said neck to be compressed between said neck and said flange to seal said joint therebetween. 